Coil clutch with resilient latch



COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964 9 Sheets-Sheet 1 firejzz ar Ran er-1 8. Beans Oct. 11, 1966 R. B. BEARE 3,277,986

COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964 9 Sheets-Sheet 2Oct. 11, 1966 BEARE 3,277,986

COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964 9 Sheets-Sheet 5 1,J6 REC/RCULAT'E '1 SYSTEM .SPl/V ROTATION (REVERSE) ONE \SNUBBEI? I I II i I DRAIN SYSTEM J5 Roerf 5. Beard V RE VERSE 9&7

Oct. 11, 1966 R. B. BEARE 3,277,986

COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964' 9 Sheets-Sheet 4WE/e22 1 01" R0 ban 5. Bears Oct. 11, 1966 R. B. BEARE 3,277,986

0011, cwwcn WITH RESILIENT LATCH Filed June 1, 1964' 9 Sheets-Sheet 5 'sl A c I TA TE SNUBBER DASH/ 07 SAN/BEER Oct. 11, 1966 R. B. BEARE3,277,986

I COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964 9 Sheets-Sheet 6 L'9 w fi/enior R0 Ben 888r Oct. 11, 1966 R. BBEARE con cwwcn WITHRESILIEN'I' LATCH 9 Sheets-Sheet '7 Filed June 1, 1964 mm e A Oct. 11,1966 R. a. BEARE COIL CLUTCH WITH RESILIENT LATCH 9 Sheets-Sheet 8 FiledJune 1, 1964 O u. u.

ZEW

EQFSEK xm JT QTAOENK Oct. 11, 1966 BEARE 3,277,986

COIL CLUTCH WITH RESILIENT LATCH Filed June 1, 1964 9 Sheets-sheet 9PRESSURE United States Patent 3,277,986 COIL CLUTCH WITH RESILIENT LATCHRobert ll. Beare, Herrin, Ill., assignor to Borg-Warner Corporation,Chicago, 111., a corporation of Illinois Filed June 1, 1964, Ser. No.371,312 2 (Ilaims. (Cl. 19226) The present invention relates to washingmachine drive mechanisms and more specifically to clutches used in suchdrive mechanisms.

In one commercial type of automatic washer respective wash and spinoperations of the washer are ellected through a pair of separate drivetrains receiving their rotative power from a common pulley belt-drivenby one motor. The transmission responds to motor and pulley rotation inone direction to eltect agitate operation of the washer, and to motorand pulley rotation in the opposite direction to ettect spin operationof the washer. Customarily, one-way spring clutches of the wrap-aroundtype are provided in the respective drive trains. These are operative inone direction of rotation, coupling drive in one direction of rotationand uncoupling drive in the opposite direction of rotation. It isadvantageous in certain washer operations to be able to selectivelyoperate the one-way clutches in their respective drive directions ofrotation. For example, it is necessary, if an initial suds removaloperation is utilized in a washer, to be able to selectively engage anddisengage the mechanism during spin drive of the clothes container orbasket.

It is an object of the present invention to provide improved means forpermitting selective engagement of oneway clutches of the spring type inthe wrap-around or drive direction of rotation so that at high speedshock received by the engaging member is absorbed or dissipated. Thisinvention finds particular, but by no means exclusive, use in anautomatic washer which uses a coil type spring clutch, which wrapsaround respective drive and driven shafts in one direction of rotationwhile unwrapping in the opposite direction of rotation. The inventivestructure includes selectively operable means for permitting andblocking spring drive during rotation in the direction customarilyeffecting drive.

It is a further object of the present invention to provide a one-wayclutch of the spring type for use in the spin drive train of anautomatic washer and which is selectively operable in the drivedirection. Along these lines it is an object to provide a clutch whichoperates quietly and has a long life during the repeated couplings anduncouplings encountered at high spin speeds.

It is an overall object of the present invention to provide aselectively operable clutch of the above type which is economical tomanufacture, simple to use, and easily adapted for use in drive trainsof standard automatic washers.

These and other objects and advantages of the invention will become moreclearly understood from the description of the drawings in which:

FIGURE 1 is a perspective of an automatic washing machine embodying thepresent invention;

FIGURE 2 is a sectional elevation taken along 22 in FIGURE 1;

FIGURE 3 is a plan view of the washing machine base assembly, takenalong line 33 of FIG. 2;

FIGURE 4 is an enlarged sectional elevation of a washing machine pumptaken along 4--4 in FIGURE 3;

FIGURE 5 is a vertical sectional View of the drive mechanism of thewashing machine;

FIGURE 6 is a plan view of a clutch assembly of the drive mechanism ofFIGURE 5, said view being taken along 66 in FIGURE 5;

FIGURE 7 is a plan view of a brake assembly of the 3,277,986 PatentedOct. 11, 1966 ICC drive mechanism of FIGURE 5, said view being takenalong 77 in FIGURE 5;

FIGURE 8 is a sectional view of a control for the clutch assembly shownin FIGURE 6, said view being taken along 8-8 in FIGURE 7;

FIGURE 9 is a plan view of a combination water level pressure and clutchcontrol switch;

FIGURE 10 is an elevational view of the pressure switch of FIGURE 9;

FIGURE 11 is a sectional view of the pressure switch taken along 1111 inFIGURE 10;

FIGURE 12 is a diagrammatic showing of the liquid flow and controlsystem, including respective 'fill, recirculation and drainage flowlines in the washing machine;

FIGURE 13 is a diagrammatic showing of the liquid level sensing andpneumatic clutch control arrangement;

FIGURE 14 is a perspective of a washing machine backguard includingprogramming and liquid level controls;

FIGURE 15 is an elevation of the programming control indicatingdifferent operations of two cycles of the washing machine;

FIGURE 16 is a schematic of the washing machine control circuit;

FIGURE 17 is a cam sequence chart illustrating the cycles of operationof the automatic washing machine of FIGURES 1-16, inclusive; and

FIGURE 18 is a simplified illustration in diagrammatic form of thecontrol circuit and operative units in the automatic washer of FIGURES1-16.

General Referring now to the drawings, shown in FIG. 1 is an automaticwasher 10 in which the present invention finds particular applicability.The automatic washer 10 includes an outer cabinet 11 having a top 12hingedly supporting a loading and unloading door 14 and carrying abackguard 15 on which are mounted controls for the washing machine. Asbest shown in FIG. 2, a tub 16 having an annular cover 16a is providedinside the cabinet 11 having a bottom 17 and a top opening 18 beneaththe door 14. Forming a container for clothes or other articles to bewashed is a perforate basket 19 having a bottom 20, top opening 20a andsides 21 mounted on a 'vertically disposed center post 22 inside the tub16.

Relative rotation between the tub and basket is permitted. In thepresent instance this is achieved by fastening the bottom 20 of thebasket to a center post base 24 using screws 24 (one of which is shown).The center post base 24 is anchored to a spin hub 26 which is rotatablyjournalled in a bearing assembly 28 mounted in the tub bottom 17.

For feeding water into the tub to wash or rinse the clothes, a flume 29is provided mounted in the tub cover 16a (opening 18). The flurne isconnected by a hose and conduit 30 to a water input control valve 31(see FIG. 12). In the illustrative embodiment the level of water isselected by positioning a rotatable control knob 34 which is connectedto a water level control switch 35, in the present instance a pressureresponsive switch. The pressure switch control for providing a selectedlevel of liquid in the tub is discussed in further detail subsequently,it is here noted that the selector control 34 can be moved to one ofthree positions, low, medium, or high for providing these relativelevels of liquid in the tub. (See FIGS. 1 and 9.)

To agitate the clothes during washing or rinsing, the basket 19 is heldstationary while an agitator 36 having a plurality of vanes 38 and askirt 39 is oscillated to and fro. The agitator has a central opening 40for receiving the center post 22 and is rotatably supported thereon.

t The center post remains stationary while the agitator oscillates.

After the tub has been filled to the level selected by control 34, awash cycle of operation begins. At this time reversible oscillatorydrive is transmitted to agitator 36 from a motor 41 through a firstdrive train including a lower drive assembly 42, a transmission 44 andan agitator drive shaft 45 (see FIG. 2). In the exemplary embodiment,the drive shaft 45 extends centrally through the hollow center post 22and carries a drive block 46 at its upper end. The upper end of theagitator central opening 40 is formed to engage the drive block 46 sothat the two structures turn as a unit. For maintaining the agitatorseated on the drive block, a cap 48 is threaded on a stud 49 extendingfrom the upper end of the drive block 46.

After the wash cycle is completed, wash water is pumped out of themachine and the basket 19 is spun at a relatively high speed to extractwash water from the clothes. The side walls 21 of the basket areperforated so that the water is expelled therethrough. Describing asecond drive train for effecting spin rotation of the basket 19, thelower drive assembly 42 is constructed so as to rotate the transmission44 as a unit including a transmission housing 50. The housing 50 iscoupled to the spin hub 26 which supports the center post 22 and basket19. Accordingly, spinning of the transmission effects rotation of thebasket 19.

First and second drive trains Turning to the respective drive trains inthe illustrative washing machine in more detail, the motor 41 is mountedin inverted fashion on a base plate 51 extending across the bottom ofthe washing machine 10 (see FIGS. 2, 3). The motor has a drive shaftwhich extends below the mounting plate 51 and carries a drive pulleywhich is coupled by a belt 52, in the present instance, a V-drive belt,to a pair of driven pulleys 54, 55, one pulley 54 coupled to drive thelower drive assembly 42 and the other pulley 55 coupled to drive a twinimpeller pump 56. As is explained subsequently, pump 56 operatesselectively as a recirculation pump or as a drain pump. Each of thedriven pulleys are disposed below the base plate 51 while the drivenmechanisms, the lower drive assembly 42, and the pump 56 are mountedatop the base plate 51. The driven pulley 54 is suitably fastened, inthe present instance by a spline and key fit (see FIG. to a main driveshaft 58 extending upwardly from the pulley 54 through the lower driveassembly 42. The upper end of shaft 58 is coupled via an overrunning orone-way spring clutch 59 to a transmission including a drive pinion 60.The transmission is shown and described in Gerhardt et al. US. PatentNo. 2,807,951, assigned to Borg-Warner Corporation. The one-way springclutch 59 provides drive to the transmission drive pinion 60 to transmitan oscillatory drive to the agitator during forward rotation of driveshaft 58, while disconnecting drive to pinion 60 during reverse rotationof shaft 58. Accordingly, to effect oscillation of the agitator, thedrive shaft 58, as a part of the first drive train, is rotated in aforward direction thereby operating the one-way clutch 59 so that thegear train in the transmission 44 effects oscillation of agitator driveshaft 45.

. Brake As described, the basket 19 is rotatable with respect to the tub16. It is, however, undesirable during the agitation cycle to have thebasket freely moving. On the other hand, washer operation is smoothedand motor strain is reduced by permitting slight movement of the basketat the point where the agitator reverses direction in its oscillationoperation. In addition, following high speed spin of the basket,structure must be provided to slow down the basket. Thus, the seconddrive train includes a brake assembly 64 to retard movement of thetransmission housing and thereby the basket 19 during agitation (seeFIGS.

5, 7). The brake assembly and its operation are the subject ofco-pending application of Clarence M. Overturf and Richard L. Conrath,Ser. No. 371,347, filed June 1, 1964. As explained, agitation drive isthrough the first drive train. The brake assembly 64 includes a brakehub 69 suitably fastened, in the present instance by a clamp 70, to abasket tube 71 coaxial with drive shaft 58 and rotatably held withrespect thereto by a bearing 72. A hub 73 is cast on the upper end ofthe basket tube 71. The hub 73 is mounted on the lower end of thetransmission housing 50. Accordingly, the tube 71 and the transmissionhousing operate as a unit, thus by holding the tube 71 stationary thetransmission housing and basket are held against rotation.

To retard basket rotation, the brake hub 69 is surrounded by a brakelining 74 which is tightly held against the hub by a brake band 75, inthe present instance constructed of spring steel. As shown in FIG. 7,braking is eifected by selectively holding the brake band againstrotation by engaging it with a brake latch 76. For this purpose thebrake band has an integral tang 78 engaging a projecting finger 79 onthe latch 76. The latter is pivotally mounted on a brake latch pedestal80 depending from a support bracket 81. The bracket 81 is mounted on asuspension tube 82 which is supported in a bearing 83 carried in thebrake hub 69.

The brake latch 78 is normally biased so that the finger 79 engages thebrake band tang 78. To this end, a biasing spring 84 is carried by thebrake bracket to pivot latch 78 about pedesal 80. The illustratedstructure permits engagement of the brake during rotation of the brakeband 75, and therewith basket 19, in either the forward or reversedirections. To engage the brake during forward rotation of the driveshaft, the agitate direction, the brake band tang 78 is received in alatch recess 79a partially formed by a side of projecting latch finger79. The provision of a recess 79a assures the holding of the brake bandand thereby retarding basket 19 against rotation in either direction. Toengage the brake in the reverse direction of rotation of the brake band,necessary during high speed spin of the basket, face 78a of tang 78 isengaged with face 7% of finger 79. The particular problem of engagementof the two faces at high speeds without throwing the latch, is solved,in the illustrative embodiment, by undercutting face 78a. As shown inthe drawings, the face 79b of the finger receives a component of forceacting substantially in line with the latch pivot point at pedestal 80.Concentrating the point of impact by using an undercut tang face 78asubstantially eliminates components of force acting to pivot latch 76about pedestal and throwing the latch so that the tang is not engaged.

Free rotation of the brake hub and appended structure, i.e. transmissionhousing and basket, is permitted by disengaging the latch 76 and thebrake band '75. For this purpose a solenoid '84 has an armature 85linked by a hook 86 to the brake latch 78 to act against the springbiasing force. Thus, when it is desired to spin the basket, thetransmission housing is freed for rotation by energizing the brakesolenoid 84 and releasing the brake 64.

Supporting the tub is an inverted generally frustoconical shaped support73 tapering down from the peripheral edge of the tub bottom to thebracket 81 and suspension tube 82 (FIG. 2). To permit limited movementor tipping of the tub, basket and drive mechanism from a vertical axiscaused by unbalanced washer loads, yet to dampen any vibration, thebracket 81 is snubbed by a set of four damping assemblies which, in thepresent instance, connect the bracket holding the tub support 16b to therespective four corners of the base plate 51. Details of the snubber ordamping assembly structures do not comprise any part of the presentinvention and thus are not described in detail herein but the structureand its effectiveness in smoothing machine operation are described inthe Gerhardt et al. US. patent, supra.

In accordance with the present invention, the second or spin drive'trainis selectively operated during reverse rotation of the motor by engagingor disengaging a clutch assembly 87 and the shock applied to the clutchat high speeds is absorbed or dissipated to increase the life and thedevice and permit quieter operation. In the present instance clutchassembly 87 transmits drive from a lower drive hub 88 to the brake hub69. As has been explained, the brake hub is coupled to the transmissionhousing 50 through the basket tube 71. The lower drive hub 88 isspline-fitted on .the main drive shaft 58 and held thereon by, forexample, a set screw (not shown). The clutch assembly 87 includes alower drive shaft or column 89 and an upper driven shaft or column 90.The lower drive column 89 is an integral extension of the lower drivehub 88. The upper driven column is a depending extension of the brakehub 69. The ends of the two columns abut opposite sides of a bearing 91which permits relative rotation .therebetween. A clutch spring 92 hasrespective upper and lower sections 92a, 92b which extend over therespective end portions of the generally abutting upper driven columnand lower drive column.

The clutch spring 92 is of the coil type and surrounds the respectivecircular drive transmitting columns or shafts. Rotation of the lowerdrive column 89 in one direction (presently, reverse motor direction)causes the clutch spring 90 to tighten and wrap-around both columns.This effects transmission of drive from the lower column 89 to the uppercolumn 90. Rotation of the lower drive column 89 in the oppositedirection (forward motor direction) uncoils or loosens the spring sothat drive is not transmitted to the upper column 90.

Selective driving in the wrap-around or drive direction is effected byuse of control means including annular means coaxial with the seconddrive train taking the form, in the exemplary embodiment, of a clutchshield or sleeve 93 extending about the spring 92 and holding aterminating end 92c of the lower spring section 92b overlying a portionof lower drive shaft 89. (See FIG. 5.) The shield or sleeve 93 andspring 92 are selectively held against rotation, as shown in FIG. 6, byproviding on the upper end of shield 93 engageable means, exemplarilyshown as a plurality of projecting ears 93a, which permit coupling witha selectively operable pivoted clutch pawl 94. The pawl 94 is normallybiased by a spring 95 so that a projecting finger 96 can engage one ofthe ears 93a. FIG. 5 shows the pawl finger 96 disengaged, and FIG. 6shows the pawl finger 96 engaged with an ear 93a. The result of holdingthe control shield or sleeve 93 stationary is, that even though thespring 92 fits snugly about the lower drive shaft or column 89 and theupper driven shaft or column 90, the spring is not tightened and driveis not transmitted from column 89 to column 90, until the spring andshield are released and permitted to rotate with the drive column.Accordingly, the present invention permits precise, selective spindriving of the basket 19.

Describing the structure for selectively engaging the clutch spring 92,the shield 93 is released and the spring is permitted to wrapearound therespective drive and driven columns 89, 90 by operation ofelectromagnetic means, here shown as a solenoid 98. It is, of course,understood that the driven column must be rotating in the properdirection to effect tightening of the spring about the respectivecolumns (see FIG. 3). The solenoid 98 has an armature 99 connected bylinkage assembly 100 to the clutch pawl 94. The solenoid acts againstthe bias spring 95 and pivots the pawl to disengage it from shield 93.

The clutch assembly is carried on a sub-support bracket 87a fastened tosupport bracket 81. The bracket 87a carries a pivot post 94a on which iscarried the pawl 94, and also an anchoring opening 954! for receivingone end of biasing spring 95. The other end of biasing spring isconnected to the pawl and held against sidewise move ment when the pawlpivots by a retainer post 95b.

To cushion the engagement of the clutch thereby adding to its long lifeand quiet operation, an elongated opening 94b is provided in the pawl 94to fit onto the pivot post 94a and permit sliding movement as well aspivotal movement relative to post 94a. The spring and pivot post 94a aredisposed so that upon engagement of the pawl and shield, for example,during high speed spin rotation of said second drive train, the pawl ispermitted limited tangential movement relative to said shield or sleeve.The linkage arm a pivoted at its opposite ends and aligned off-centerguides this movement so that the pawl remains engaged and the pawlfinger 96 does not slip off the particular ear 93a to which it iscoupled. Thereby, the rotational inertia possessed by the second drivetrain, which is high at the moment of engagement of the pawl, isabsorbed without applying high stress to the pivot post 94a.

Turning to the motor 41, it is reversible to rotate pump 55 and maindrive shaft 58 in either direction. The motor has a stant winding 41aand a pair of run windings 41b, 410 (see FIG. 16). Direction of rotationis determined by the relative polarity between the start and runwindings, i.e. simply by reversing the relative polarity rotation of themotor is reversed. Only one run winding is used at a time, energizationof winding 41b gives normal speed operation while winding 41c gives slowspeed operation.

Energization of .the motor winding is controlled by a control circuit101 in response to operation of a programmer in the present instance, atimer or sequential controller 102 (FIG. 18). As shall be explained indetail subsequently, timer 102 instructs circuit 101 by operatingappropriate switches therein to control the washer operations asexemplarily set out on timer dial 102a, i.e. wash and extraction, thelatter including respective rinse and spin dry cycles.

Upon receiving wash or agitate instructions the control circuit 101effects mot-or rotation in a forward direction to rotate the shaft 58and thereby drive the transmission gear train through the one-way clutch59 to oscillate the agitator 36.

In response to spin instructions the control circuit 101 reverses thedirection of motor rotation. As explained, the transmission one-wayclutch 59 is inoperative in the reverse direction of motor rotation,thus oscillatory drive is not transmitted to the agitator. The controlcircuit first energizes brake solenoid 84 to release brake 64 permittingfree movement of the basket 19 and housing 50. Subsequently, uponoperation of liquid level sensor switch 35, as explained in a later partof the specification, the circuit energizes the clutch solenoid 93 toengage clutch 87 so that a drive connection is completed for rotatingthe transmission housing and spinning the basket 19.

Pump

To recirculate water during the washing operation and to drain waterprior to the spinning operation, the pump 56 is provided (see FIG. 4).This is a dual impeller pump having an upper impeller 103 and a lowerimpeller 104. The impellers are carried on a common shaft 55a the lowerend of which holds the pulley 55 coupled to the motor by V-belt 52. Inone direction of rotation the upper impeller recirculates water via asystem 105 and in the opposite direction of rotation the lower impeller104 drains water through a system 106.

The respective recirculation and drainage systems 105, 106 are bestshown in FIG. 12. A hose 107 couples the recirculation impeller 103 tothe lower part of the side of tub 16. The connection is just above thebottom of the tub so that soil, pebbles, and like materials are notrecirculated. An output hose 108 returns the water to the tub 16 througha fiume 108a located adjacent the tub top (see FIG. 2).

To remove or drain liquid from the tub, control circuit 101 intiatesreverse rotation of the motor to effect liquid pumping operation ofdrain impeller 104. A hose 109 couples the drain impeller to a sump 110at the bottom of tub 16 to draw water out. The wash or rinse water isforced out by the lower impeller into a drain hose 111 and carried to anoppropriate drain connection (not shown).

During forward rotation of pump pulley 55 and while upper impeller 103is recirculating water in the tub, the lower impeller 104 is acting soas to draw air through hose 111. As preferably constructed the lowerimpeller 104 will not draw liquid from the sump 110 during forwardrotation of pump pulley 56.

In the opposite direction of pump pulley rotation, reverse direction asocurs during spin operation of the washer and while lower impeller 104is removing water from the tub, the upper impeller 103 is drawing airthrough hose 108. In the preferred embodiment, the upper impeller willnot draw liquid from tub 16 during reverse rotation of pump pulley 56.The pump is described in further detail in Pinder, US. Patent No.2,938,130, issued May 9, 1961.

Control circuit As noted, the overall operation of the washing machineis controlled by the programmer 102 instructing a control circuit 101.The programmer is a time-motor TM operated unit which closes and opensrespective contacts in timed sequence so as to effect specificoperations in the control circuit. The timer structure is explained infurther detail in copending application of Carl J. Knerr, Ser. No.254,640, filed Jan. 29, 1963. In order to facilitate understanding ofthe programmer and control circuit a simplified diagram of the controlsystem and coupled mechanical structure is presented in FIG. 18.

The timer sequence chart of FIG. 17 illustrates the contacts of switchesthat are opened and closed at any given position of timer operation. Toestablish exactly the electrical components functioning at any giventime during specific cycles of machine operation, it is only necessaryto establish which sequences are of interest and then to identify theswitches that are closed as represented by the dark squares on the timersequence chart. Each individual energizing circuit, during a givenperiod, may thus be identified by using the timer sequence chart andreferring to the switches in the electrical circuit schematic in FIG.16.

Turning to the control circuit 101 and FIGS. 16, 17, and 18, it effectsoperation of the mechanical units of the washer in automatic sequencethrough a cycle of operation as set forth in the chart of FIG. 17. Asource of electrical power represented by the term line between a pairof conductors C1, C2 energizes the circuit when contacts PPS of amanually operable push-pull switch 112 are closed. To provide anemergency stop when the machine top door 14, is opened, a door actuatedswitch having contacts DSW is provided. This is necessary during highspeed spinning of basket 19 to prevent the person opening the door frombeing injured. The brake solenoid 84 is immedately deenergized to effectbraking and the clutch solenoid 98 is deenergized to disconnect spindrive of the basket. It is desirable, however, during the wash and rinseoperations of the machine cycle that access be permitted to the tub andbasket without stopping the machine. Thus a set of door by-pass switchcontacts SW1 are provided and, as shown in the chart of FIG. 17, theseare closed during the wash and agitate operations of the machine.

The programmer 102 initially prepares the circuit 101 for feeding waterinto tub 16. The desired temperature of the wash water is selected byoperating a knob 114 which controls a set of switch contacts WSW. Theswitch contacts can be moved to either the following positions: whereonly a hot water valve solenoid 115 is energized; where only a coldwater valve solenoid 116 8 is energized; or where both solenoids 115,116 are energized to feed warm water into the tub. The respective 'hotand cold water valves are contained in the main water valve which isthereby coupled to the circuit so that water input to the tub can becontrolled, either turning it on or turning it off. The energizingcircuit for the water valve solenoids includes a contact assembly PSW ofpressure switch 35, specifically a contact PSWa, and a pair oftimer-operated switches SW1 and SW4, the latter having contacts a and bto provide selective isolation of the hot water supply during rinseoperation of the machine (C1SW1PSWa-SW2-WSW-SW4a-115 or 116-PPS- C2).The pressure switch 35 remains on contact a until the water level in thetub is high enough to apply a pressure to the switch and put the switchon contact b. This deenergizes the water valve solenoids to close thevalves and shut off the water flow. The details of the pressure switchare given later.

The motor windings 41a, 41b, 410 are selectively coupled to theenergization source by the control circuit 101. The motor is rotated inthe forward direction to effect agitation and recirculation in themachine when the pressure switch moves to contact PSWb. Explaining themotor energizing circuit, the timer instructs the closing of a switchcontact SW7. A contact SWSa is normally closed and connected by aconductor C3 to the motor run winding 41b. The motor run windingenergizing circuit includes (c1-SW1-PSWb-SW7-SW8a-C3-41b-PPS C2). Forenergizing the start winding 41a, a pair of respective contacts SW10aand SW11a are normally closed. Contact SW10a is connected into the C1side of circuit 101 by a conductor C4 and through a normally closedswitch SW9 to start winding 41a. The winding 41a is connected to the C2side of circuit 101 via a conductor C5, switch contact SW11a and aconductor C6 and the switch PPS (C1SW1PSWbSW7-SW8aSW10aSW941a-C5-SW11a-C6-PPS-C2). The switch SW9 is responsive to motor speed,i.e. centrifugal switch, deenergizing the start winding when the motorreaches a predetermined speed. Switch contacts SWSa, SW8!) are part of amotor speed selector 122. By operating speed selector 122 to closecontact SW8b winding 410 is energized and a slow speed motor operationduring the wash cycle can be obtained.

The timer motor TM powering the timer 102 is energized through anormally closed contact SW64; C1-SW1 PSWb-SW6a-TMPPSC2) Turning to thechart in FIG. 17, it is noted that in the exemplary regular cycle ofoperation, during the wash cycle the control circuit switch contactsSW1, SW2, SW4a, SW6d, SW7, SWIM and SW11a are closed. In the presentinstance the timer 102 maintains a Wash cycle for 10 minutes. At the endof the cycle contacts SW2, SW7, SW10a are opened. There is a pause of 1minute permitting the motor to decelerate and stop before it isenergized for reverse rotation.

To reverse the motor, the timer closes contacts SW12, SW10l1, SWllb. Asis clear from the circuit diagram of FIG. 16, closing of contact SW12completes an energizing circuit for the motor run winding 41b through anormally closed switch contact SW13a (C1DSWSW12SW13a 41b-PPSC2). Theclosing of contacts SW10b and SWllb reverses the phase of the power instart winding 41a as compared to what it was when contacts SW10a andSW11a were closed (C1SW12SW13aC3-C4- SWllb C5 41a SW9-SW10b-C6-PPS-C2).Switch SW13 is also a part of the speed selector 122 and either contactSW13a can be closed for normal motor speed operation or contact SW13!)can be closed for slow motor speed operation. This provides a fast andslow drive to spin basket 19.

Reverse rotation of the motor, effected by the control circuit inresponse to spin instructions from the timer 102, stops recirculationoperation of pump 56 and starts drain operation of impeller 104. Liquidis thereby removed from the tub.

131 joins sump 110.

As part of the spin instructions, the timer 102 closes a contact SW14 inthe control circuit 101 to energize brake solenoid 84(C1-DSWSW14-84PPSC2). The by-pass switch SW1 is open making the switchDSW eifective to deenergize the circuit 101 should the door be opened.In the energizing circuit for the clutch solenoid 98, contact SW15a isclosed. However, the circuit 101 will not energize the clutch solenoiduntil the pressure switch contact PSWa is closed as well as asub-interval switch SIS (C1DSWPSWa-SISSW15a98PPS-C2). The pressureswitch 35 maintains contact PSWb closed and PSWa open until the liquidlevel in the tub is lowered to a predetermined point whereupon contactPSWa is closed. In practice it has been found to be advantageous tolower the liquid below the point at which connector As a part of abasket acceleration and coast operation explained later, the switch SISis closed for a short time interval.

The timer motor TM is deenergized at the beginning of the spin cycleafter reverse rotation of the motor 41 has begun and pump 56 is drainingliquid from the tub. Deenergization occurs when the timer 102 openscontact SW6a and closes contact SW6b. The timer motor is not energizedagain until the tub is empty and pressure switch contact PSWa is closed.Accordingly, there is not a fixed time in which the tub must empty.

Liquid level sensor and control To transmit tub liquid level informationto control circuit 101 a tub liquid level sensor, in the presentinstance a fluid circuit 130, operates switch 35 (see FIG. 13). Becausethe illustrative sensor is of the pressure type a pressure type switch35 is used. It is understood that other liquid level sensors could beutilized. The fluid circuit senses the water level as represented by ahead of water in the tub 16 and transduces this information into apressure in an air pressure tube 132. The latter is coupled to the drainsump 110 at the bottom of the tub by a connector conduit 131. Waterseeking the same level in the fluid circuit 130 as in the tub 16 trapsair in the upper portion of the tub 132 and compresses it.

As best shown in FIGS. 9, 10, and 11, the air tube 132 is connected totransmit the air pressure therein to pressure switch 35 and operatecontacts PSWa and PSWb. In the present instance the pressure switchincludes a hub-shaped annular body 135 having opposite open ends with acomplementarily shaped and generally concave cover 136 fitted over thelarger of the open ends. A diaphragm 138 of flexible material, forexample rubber, is installed to form a wall between the body 135 andcover 136 and define a pair of separated chambers 139, 140 within thebody-cover enclosure.

The fluid circuit tube 132 is coupled to a fitting 141 carried by thecover 136. Accordingly, air pressure variations in the fluid circuiteffected by changes in the tub water level are applied as a force toflex the diaphragm 138. To prevent momentary pressure build-upsresulting, for example, from a toroidal column of water created aboutthe tub sides during spinning of the basket, from acting on thediaphragm an orifice 161 is provided in fluid line 132. The restrictionto air flow thereby effected absorbs surges of pressure due to transientliquid level conditions in the tub.

Responsive to movements of the diaphragm is a switch mechanism 142 inchamber 140 including a slidable switch block 144 operating a movablesnap or toggle switch element 145 which closes respective ones of thepressure switch contacts PSWa, PSWb. The switch block is biased by aspring assembly 146 to act against the pressure force applied todiaphragm 138 and transmitted to the block by a plate 138a centrallycarried by diaphragm 138.

The block 144 and spring assembly 146 are carried in a rearwardlyextending cylindrical portion 148 of the switch body 135, the block 144being biased toward the diaphragm 138 by a spring 149. The rear end ofspring it 149 is received in a cap 150 and both fit into the cylindricalopening in rear body portion 148. A lever and screw 151, 151arespectively, act on the cap to maintain a spring force on the block.

Manual selection of spring compression and thereby the pressurenecessary in fluid circuit to actuate switch contacts PSW to closecontact PSWb is made by pivotally positioning lever 151. To this end abracket 152 is mounted on the switch body and a control shaft 153 isrotatably carried between upstanding arms 154, 155. Lever 151 ispivotally supported by arm 155 and shaft 153 carries a cam 156 having acamming surface 156a engaging one end of lever 151 to pivot it and applyor release compressive force on spring 149. The rotatable water levelcontrol 34 is connected to the shaft 153 and, in the present instance,can be manually turned to one position rotating the shaft andcompressing the spring so that the switch does not trip until the tub isfilled to a high level or turned to other respective positions releasingthe spring and thereby adjusting the controls for automatic fill of thetub to medium or low levels, respectively. The screw 151a permitsinitial adjustment of the pressure switch so that the respective waterlevels at which the switch 35 trips, i.e., low, medium and high,correspond to desired water levels in the tub.

After the movable element in switch 35 is actuated and contact PSW]; isclosed in response to the tub filling with liquid to a predeterminedhigh level or point, the contact remains closed until the liquid islowered whereupon the switch resets or returns to contact PSWa. In otherwords, the element 145 is actuated from a first position, contact PSWaclosed, to a second position, PSW]; closed and PSWa open, in response toa selected high liquid level in the tub. To provide a substantiallyconstant reset or return pressure corresponding to a predetermined lowliquid level in the tub and sump, the switch block 144 is biased by asecond independently adjustable spring assembly 157. Thus, regardless ofwhat pressure is required to trip the switch and stop liquid input tothe tub, the switch will not return from its second or tripped position,PSWb closed, to its first or reset posi- It is clear from the foregoingthat in the ordinary operation of the washer, the liquid level sensorswitch 35 is actuated to its second position when the tub is filled tothe selected level. This occurs before spin instructions are transmittedto the control circuit 101, indeed before the wash-agitate cycle begins.When the liquid level is lowered below a predetermined point, the switch35 returns or resets to its first position and circuit 101 is ready toengage clutch 8'7.

Assume, however, that the sequential control dial 102a is advanced tothe spin position by a housewife having decided not to Wash her clothesduring filling of the tub and while switch contacts PSW of switch 35 arestill in their first position. As noted, the contacts PSW of switch 35in their first position effect spin drive of the basket. This wouldflush the liquid out of the tub and most likely overload the motor.

To prevent the occurrence of these events, the preferred embodimentutilizes a safety control to insure that the liquid level in the tub islowered to a predetermined low level before the spin drive to the basketis engaged to prevent spinning of the basket when the tub is partiallyfilled with liquid. The safety control is the subject of a copendingapplication of Carl J. Knerr, Ser. No. 371,245, filed June 1, 1964.

As herein illustrated, the safety control includes a supplementalpressure creating means, exemplified by dashpot 160, to actuate pressureswitch contacts PSW from their first position, maintained during fillingof the tub, to their second position, assumed ordinarily when the tub isfilled to the selected level. Thus, in effect, the safety controlsimulates a high liquid level condition in tub 16.

As can be seen from the circuits in FIGS. 16 and 18, the respectivefirst and second switch positions are here shown as PSWa and PSWbrespectively. The clutch solenoid cannot be energized until the switchPSW is actuated or reset and contact b is opened while contact a isclosed. This occurs only after the pressure applied to pressure switch35, including the water level pressure and the supplemental pressure,bleeds down from fluid circuit 130. Bleeding of the air pressure occursas the head of liquid in the tub is lowered by the pump 56. Drainoperation of the pump occurs immediately upon the feeding of spininstructions to circuit 101. The orifice 1611 is helpful in restrictingthe escape of fluid out of a pressure switch portion 130a of fluidcircuit 130. Thus, operation of the dashpot 160 in setting the switchcontacts PSW is aided.

Describing the supplemental pressure creating dashpot 160, as best shownin FIG. 8, it includes a housing 164 and a cover 165 which, assembled,define a pair of enclosures 166, 16 8 separated by a movable diaphragm169, in the present instance constructed of suitable flexible materialsuch as rubber. 'Io eifect operation of the dashpot in response to spininstructions from the programmer, in the illustrative embodiment a shaft170' is slidably received in an end wall of the housing 164 and couplesthe brake solenoid armature 85 to the diaphragm 169. The diaphragm 169has a centrally positioned plate 171 of inflexible material which theend of shaft 170 acts upon. The diaphragm 1 69 is biased in a normalposition by the spring 172 in the chamber 168. 9

Upon actuation of the brake solenoid armature initiated by spininstructions from the programmer, the shaft 170 acts against thediaphragm plate 171 and the biasing force of spring 172 to move thediaphragm and force air through a conduit 174 coupling the dashpot 1 60to the pressure switch 35 and the tube 132 of the fluid circuit 130. Thefluid circuit is divided by orifice 161 into the pressure switch portion130a and a tub portion :130b. As here shown, in order to mostefliciently utilize the movement of dashpot diaphragm 169 to apply aforce on pressure switch diaphragm 138 the dashpot 160 is connected intothe pressure switch side 130a of fluid circuit 130. Thus, the pressureimpulse effected by operation of the dashpot 160 acts on the diaphragm138 of pressure switch 35 to set the contacts PSW in their high liquidlevel position.

The present invention is particularly useful if the housewife advancesthe timer knob 1012a to spin operation during filling of the tube eitherin the wash cycle or in the rinse-agitate cycle. Such advances of theknob 102a feed spin instructions to the control circuit 101 while thepressure switch PSW is still in its first or empty position and thecircuit would respond by coupling the second drive train for spinningthe basket while the tub is still partially filled with liquid. Thepresent invention assures that the basket is not spun until the liquidin the tub is lowered to the predetermined low level. The safety controlsets the liquid level sensor switch in the tripped or high liquid levelposition so that the washer proceeds through the customary cycle ofliquid removal before the spin drive to the motor is engaged.

The terms high liquid level and low liquid level used in describingresponsive movements of switch PSW in sensing liquid level in tub 16 arenot to be confused with marked settings for the water level control 34.The H, M, and L settings of the latter identify relative levels to whichthe tub is filled before switch PSW is actuated. Thus, even though therelative tub liquid level may be low because the control is set to L,the switch PSW senses the top of the tub liquid level as a high liquidlevel. The reset bias assembly 157 in the pressure switch 35 assuresthat the same low liquid level trips the switch upon each lowering ofthe liquid level in the tub.

The regular cycle of operation for a washer has been explained up to thepoint where the programmer 102 has instructed control circuit 101 toenergize motor '41 so it rotates in reverse thereby operating pump 56 toremove wash water from the tube 16. The circuit has been prepared toelfect spin rotation of basket 19. That is switch SW14 is closedenergizing brake solenoid 84 and releasing the second drive train fortransmitting drive to the basket, and clutch solenoid switch contactSWlSa is closed. The liquid level sensor switch PSW is in its firstposition with contact PSWa closed. The timer motor TM has beendeenergized to allow the pump 56 all the time it needs to remove theliquid from tub 16. When the pres-sure switch resets to its firstposition the timer motor is again energized to operate its associatedcams in programmer 102. At a preset time in the washer cycle, the timeractuates the sub-interval switch SIS, and since contact PSWa is closedthe clutch solenoid is energized and the clutch engaged to spin thebasket.

In order to effect initial suds removal including wash water trapped inthe clothes after the pump 56 has drained the tub, the followingprocedure is followed for spinning the basket and introducing rinseliquid. The structure and procedure is the subject of a copendingapplication of R. Waldrop, Ser. No. 371,670, filed June 1, 1964. First,even though switch SWlSa is closed, the clutch solenoid 98 is notenergized until the timer actuated sub-interval switch SIS is closed.-In the present instance the switch SIS is close-d for 15 seconds toaccelerate the basket to a portion of full speed and then coast. Duringthis acceleration and coast period wash water and suds trapped in theclothes are ejected by centrifugal force.

A switch contact SW16a is closed after the basket has been acceleratedand while it is coasting to operate the Water valve solenoids 115, 116and introduce fresh water through valve 31 for one minute into the tubthereby diluting the suds and wash water and preventing sudslock. Thetemperature of the rinse water is selected by adjustment of a rinsewater switch RSW which operates in the same manner as the wash waterswitch WSW, previously explained. Preferably only cold water is used inthis rinse operation. As is clear from the sequence chart of FIG. 17,while the switch SW16a energizes the water valve solenoids through therinse water temperature selector switch RSW and switch contact SW41),the motor is rota-ting in the reverse direction and, even though thebasket is not connected thereto because the clutch solenoid '98 is notenergized, the pump 56 is operating in reverse removing the rinse andwash water from the tub.

The pump operates for the full five minutes of the Initial Suds Removalwasher program period. Because the motor is operating at full speed,except when slowed down during the interval engagement of clutch 98, thepump 56 is operating at full capacity. This assures efi'icient and quickremoval of sudsy liquid and further aids in preventing suds lock. Thisempties the tub and prepares the machine for subsequent spinning of thebasket.

For the last two minutes of the Initial Suds Removal period the basketis spun to force out additional amounts of suds and wash water after thespray down with fresh water. T 0 effect spinning as is shown in thechart of FIG. 17, the switch SW14 energizing the brake solenoid isclosed and the brake is released so it is only necessary to engageclutch 87. To energize the clutch solenoid 98 independently ofsub-interval switch SIS, switch SW15 is moved so as to close contact bthereby connecting clutch solenoid 98 across electrical sourch C1C2(C1DSW PSWa-SW15b98PPS-C2 After the two minute spin completing theInitial Suds Removal period, the motor switch SW12 is opened for oneminute to permit the motor to coast to a stop. During this last minutethe rinse water switch conact SWlSa is closed thereby operating waterinput control valve 31 and filling the tub with rinse water. The liquidlevel sensor operates switch 35 and closes contact PSWb when the rinsewater in the tub has reached a lever corresponding to that preset byliquid control 34.

Next the timer operates the contacts SW7, SW10, SW11 to energize motor41 for rotation in a forward direction. The first drive train isoperative to oscillate the agitator while the tub is full of rinsewater. As can be seen from the chart of FIG. 17 the brake solenoidswitch SW14, the clutch solenoid switch SW15 are open. Thus thesolenoids are deenergized and the circuit 101 is in the same state as itwas during the wash cycle except that the wash water switch contact SW16a is closed. While the motor is rotating in the forward direction, therecirculation system 105 of pump 56 is operative.

The rinse agitate cycle continues for four minutes whereupon the forwardor agitate direction motor control switch contact SW7 is opened by timer102 deenergizing the motor and stopping the agitator. There is a oneminute pause before the next operation.

As a last step the motor is rotated in reverse by closing motor controlswitch contact SW12 and contacts SW10b, SW11b. (The energizing circuithas been described before.) The liquid removal system 106 of pump 56 isput into operation to empty the liquid from tub 16. The brake solenoid84 is energized by closing contact SW14 releasing the second drive traintfor spinning the basket 19. The liquid level sensor switch 35 isactuated when the tub empties, opening contact PSWb and closing PSWa,and clutch control switch contact SW15]; is closed completing a circuitfor energizing clutch solenoid 98 and engaging the second drive train.The basket 19 is spun, in the illustrated washer program, for sixminutes. During this time the pump 56 is operated, the drain system 106being utilized to remove liquid from tub 16.

To permit manual selection of washer programs as set out on the dial102a, a mechanical coupling (not shown) is provided between the controlknob 112 and the dial. Turning the knob elfects rotation of the dial toselected programs as shown by legends on the dial 102a.

What is claimed is:

1. In a washing machine having a tub for receiving and holding a liquidand a basket rotatably supported in the tub to form a container forclothes and the like, the basket coupled to a motor through a drivetrain, the subcombination comprising a drive shaft in said drive train,a driven shaft axially aligned with, and disposed in generally abuttingrelationship to said drive shaft, a clutch spring having opposite endsand respective axial sections overlying adjacent portions of saidrespective drive and driven shafts and snugly fitting therea'bout, saidspring coiled to wraparound both shafts in response to drive shaftrotation in one direction and to unwrap in response to drive shaftrotation in the opposite direction, annular means coaxial with saiddrive train and connected to said one spring end terminating said springsection overlying said drive shaft, said spring carrying said annularmeans therewith when said drive shaft rotates said spring, ears carried'by said annular means, a latch pivotally mounted on a pivotal mountingso as to move toward and away from said annular means, projecting meanscarried by said latch to engage said ears to hold said annular means andconnected spring against rotation in said spring wraparound direction,and said latch privotal mounting including means to permit movement ofsaid latch to absorb the shock received by the latter when engaging saidannular means rotating at high speed.

2. In a washing machine having a tub for receiving and holding a liquidand a basket rotatably supported in the tub to form a container forclothes and the like, the basket coupled to a motor through a drivetrain, and a stationary support bracket disposed adjacent said drivetrain, the sub-combination comprising a drive shaft in said drive train,a driven shaft axially aligned with, and disposed in generally abuttingrelationship to said drive shaft, a clutch spring having opposite endsand respective axial sections overlying adjacent portions of saidrespective drive and driven shafts and snugly fitting thereabout, saidspring coiled to wrap-around both shafts in response to drive shaftrotation in one direction and to unwrap in response to drive shaftrotation in the opposite direction, annular means coaxial with saiddrive train and connected to said one spring and terminating said springsection overlying said drive shaft, said spring carrying said annularmeans therewith when said drive shaft rotates said spring, ears carriedby said annular means, a pivot post carried by the support bracket, alatch having an elongated opening for receiving said post and disposedto one side of said drive train for pivotable movement toward and awayfrom said annular means, a biasing spring carried by the support andacting to normally pivot said latch toward said annular means, andprojecting means carried by said latch to engage said ears to hold saidannular means and connected spring against rotation in said springwrap-around direction, said elongated opening permitting said latch toslide substantially tangentially with respect. to said annular meansupon engagement of said latch so that the rotational intertia of saiddrive train is absorbed in said biasing spring.

References Cited by the Examiner UNITED STATES PATENTS Re. 25,229 8/1962Sacchini et al 192-26 X 1,927,060 9/ 1933 Ballard 192-27 2,813,60811/1957 Caburet 192-28 X 2,872,828 2/1959 Brogdon 192--26 X 2,878,9143/1959 Worst 192-41 X 3,062,345 11/ 1962 Cruzen 19226 DAVID J.WILLIAMOWSKY, Primary Examiner.

B. W. WYCHE, III, Assistant Examiner.

1. IN A WASHING MACHINE HAVING A TUB FOR RECEIVING AND HOLDING A LIQUIDAND A BASKET ROTATABLY SUPPORTED IN THE TUB TO FORM A CONTAINER FORCLOTHES AND THE LIKE, TE BASKET COUPLED TO A MOTOR THROUGH A DRIVETRAIN, THE SUBCOMBINATION COMPRISING A DRIVE SHAFT IN SAID DRIVE TRAIN,A DRIVEN SHAFT AXIALLY ALIGNED WITH, AND DISPOSED IN GENERALLY ABUTTINGRELATIONSHIP TO SAID DRIVE SHAFT, A CLUTCH SPRING HAVING OPPOSITE ENDSAND RESPECTIVE AXIAL SECTIONS OVERLYING ADJACENT PORTIONS OF SAIDRESPECTIVE DRIVE AND DIRVEN SHAFTS AND SNUGLY FITTING THEREABOUT, SAIDSPRING COILED TO WRAP-AROUND BOTH SHAFTS IN RESPONSE TO DRIVE SHAFTROTATION IN ONE DIRECTION AND TO UNWRAP IN RESPONSE TO DRIVE SHAFTROTATION IN THE OPPOSITE DIRECTION, ANNULAR MEANS COAXIAL WITH SAIDDRIVE TRAIN AND CONNECTED TO SAID ONE SPRING END TERMINATING SAID SPRINGSECTION OVERLYING SAID DRIVE SHAFT, SAID SPRING CARRYING SAID ANNULURMEANS THEREWITH WHEN SAID DRIVE SHAFT ROTATES SAID SPRING, EARS CARRIEDBY SAID ANNULUR MEANS, A LATCH PIVOTALLY MOUNTED ON A PIVOTAL MOUNTINGSO AS TO MOVE TOWARD AND AWAY FROM SAID ANNULAR MEANS, PROJECTING MEANSCARRIED BY SAID LATCH TO ENGAGE SAID EARS TO HOLE SAID ANNULUR MEANS ANDCONNECTED SPRING AGAINST ROTATION IN SAID SPRING WRAPAROUND DIRECTION,AND SAID LATCH PRIVOTAL MOUNTING INCLUDING MEANS TO PERMIT MOVEMENT OFSAID LATCH TO ABSORB THE SHOCK RECEIVED BY THE LATTER WHEN ENGAGING SAIDANNULAR MEANS ROTATING AT HIGH SPEED.